1. Field of Invention
The present invention relates to an assembly structure of side members of a vehicle and a front end module thereof assembled to the front ends of the side members.
2. Description of Related Art
Formerly, headlamps and heat-exchanger equipment such as a radiator are attached to or installed on a pre-assembled vehicle body in a former assembly line, specifically to a radiator core support connected to body side members. Therefore, increase in the number of parts to be attached or installed complicates the work performed on the assembly line, lowering the work efficiency.
Recently, in order to improve the work efficiency in the final assembly line, headlamps and heat-exchanger equipment such as a radiator and a capacitor are preliminarily attached to or installed on a radiator core support to form a front end module in a line other than the final assembly line, for example, a line of a parts manufacturing company, and the front end module is fed to the final assembly line, as disclosed in Japanese Patent publications Nos. 2848666, 2898339, and 2907502.
As the number of equipment to be mounted onto the front end module increases, the weight thereof becomes substantially heavy, which makes it difficult for a worker to handle the front end module.
A loading jig for assisting the worker to lift the front end module is therefore provided on the final assembly line. The worker fastens rear ends of both sides of the front end module to the front ends of the side members with bolts and nuts, while lifting the front end module with the loading jig.
In this case, the rear ends of both sides of the front end module and the front ends of the side members have to be positioned accurately.
FIGS. 9 to 12 show a comparative example of a front end module assembly structure. As shown in FIG. 10, a bracket plate 7 is fixed to each of the rear ends of both sides of the front end module 5. As shown in FIG. 11, a C-shaped cut is made in the center of the bracket plate 7, and the cut portion is folded rearward so as to form an insert piece 8 in substantially a right triangular shape.
Meanwhile, an insertion hole 10 is formed in a bracket plate 9 on the front end of a side member 6 so as to allow the insert piece 8 to be inserted thereinto. When the front end module 5 is connected to the side member 6, the insert piece 8 is inserted into the insertion hole 10, and a vertical positioning of the front end module 5 relative to the side member 6 is performed. Then the bracket plate 7 of the front end module 5 and the bracket plate 9 of the side member 6 are fixed with bolts and nuts.
After fastening of the bracket plates 7 and 9, the front portion of the front end module 5 is fixed to the side member 6 with fourteen (14) bolts (seven (7) bolts for each side), and the upper rear end portions are fixed to the side member 6 with four (4) bolts (two (2) bolts for each side) as shown in FIG. 12.